Ultrasound Glossary

The backward flow of stomach contents into the esophagus, which can be observed in real time during abdominal ultrasound.

Bleeding from anywhere in the digestive tract, which may prompt ultrasound evaluation of the liver, spleen, and abdominal organs for underlying causes.

The tubular system of organs extending from the mouth to the anus that digests food, which can be evaluated with ultrasound in specific clinical situations.

A birth defect in which the fetal abdominal wall fails to close completely, allowing intestines to protrude outside the body, detectable on prenatal ultrasound.

The age of a pregnancy measured in weeks from the first day of the last menstrual period.

The first ultrasound-visible sign of pregnancy, appearing as a small, round, fluid-filled structure in the uterus at about 4 to 5 weeks of gestation.

A group of rare conditions in which abnormal tissue grows in the uterus after fertilization, including molar pregnancy, with a characteristic ultrasound appearance.

An enlargement of the thyroid gland visible as a swelling in the neck, which is evaluated with ultrasound to determine its cause and characteristics.

A painful form of arthritis caused by uric acid crystal deposits in joints, which produces distinctive findings on musculoskeletal ultrasound.

An ultrasound technique in which the sonographer applies gradually increasing pressure with the transducer to push gas-filled bowel out of the way and better visualize structures like the appendix.

A small area of inflammation caused by the body’s immune response, which can sometimes be detected as a focal lesion on ultrasound.

The range of shades from black to white used to display the varying strengths of returning echoes in a standard B-mode ultrasound image.

The longest vein in the body, running from the foot to the groin along the inner leg, frequently evaluated in venous ultrasound for insufficiency and varicose veins.

A hazy, semi-transparent appearance on ultrasound that is characteristic of certain cysts, particularly endometriomas, containing thick or old blood.

An imaging technique that uses harmonic frequencies generated within tissue to produce images with less artifact and better contrast.

A standard measurement taken around the fetal skull during obstetric ultrasound, used to estimate gestational age and assess brain growth.

A condition in which the electrical signal that controls the heartbeat is delayed or blocked, detectable during echocardiography or fetal heart monitoring.

The number of times the heart beats per minute, routinely assessed during echocardiography and obstetric ultrasound.

A benign tumor made of blood vessels, most commonly found in the liver, where it appears as a bright, well-defined mass on ultrasound.

A collection of blood within the sac surrounding the testicle, usually caused by trauma, visible on scrotal ultrasound.

A localized collection of blood outside the blood vessels, usually caused by injury or surgery, whose appearance on ultrasound changes over time.

The process of blood cell production, which occurs in the bone marrow in adults but in the liver and spleen during fetal development.

A condition in which too much iron accumulates in the body’s organs, particularly the liver, which can be assessed with ultrasound and elastography.

The presence of blood in the pericardial sac surrounding the heart, a potentially life-threatening condition visible on echocardiography.

Free blood in the abdominal cavity, commonly detected during trauma ultrasound (FAST exam) as dark fluid around the organs.

Active or recent bleeding from a blood vessel, which can occur in many organs and has a variable appearance on ultrasound depending on its age and location.

An ovarian cyst that has bled internally, creating a characteristic pattern of fine, lace-like internal echoes on ultrasound.

A pocket of infected fluid within the liver that appears on ultrasound as a complex fluid collection, often requiring drainage.

A benign liver tumor associated with oral contraceptive use that carries a risk of bleeding and a small risk of malignant transformation.

The blood vessel that supplies oxygen-rich blood to the liver, routinely evaluated with Doppler ultrasound.

A benign, fluid-filled sac within the liver that is very common, usually incidental, and has a characteristic simple appearance on ultrasound.

The bile drainage channels within and exiting the liver that carry bile toward the common bile duct and gallbladder.

A brain disorder caused by severe liver disease that impairs mental function, occurring in patients whose liver ultrasound often shows signs of cirrhosis.

The inability of the liver to perform its normal functions, which can be acute or chronic, with ultrasound used to evaluate the liver and its blood supply.

Scarring of the liver tissue from chronic damage, which can now be assessed non-invasively with ultrasound elastography.

The most common benign liver tumor, appearing characteristically as a small, bright, well-defined mass on ultrasound.

Death of liver tissue due to loss of blood supply, a rare condition that can appear as a focal area of altered echogenicity on ultrasound.

Any solid or complex lesion within the liver, which requires ultrasound characterization to determine whether it is benign or potentially malignant.

Cancer that has spread to the liver from another part of the body, the most common malignant liver tumor, with variable ultrasound appearances.

Elevated pressure in the portal venous system, identified on Doppler ultrasound by reduced, reversed, or absent portal venous flow.

The medical term for fatty liver, where excess fat accumulates in liver cells, causing the liver to appear abnormally bright on ultrasound.

One of three large veins that drain blood from the liver into the inferior vena cava, routinely evaluated with Doppler ultrasound.

The drainage of blood from the liver through the hepatic veins into the inferior vena cava, assessed with Doppler to detect obstruction.

Inflammation of the liver from viral infection, alcohol, medications, or other causes, which can alter the liver’s appearance on ultrasound.

The most common primary liver cancer, arising in cirrhotic livers and detected on surveillance ultrasound.

Enlargement of the liver beyond its normal size, which can be measured with ultrasound and may indicate various liver diseases or systemic conditions.

A rare condition causing portal hypertension without cirrhosis, in which the small portal vein branches within the liver become scarred and narrowed.

A serious complication of advanced liver disease in which the kidneys fail despite being structurally normal, with Doppler showing increased renal vascular resistance.

A protrusion of an organ or tissue through a weak point in the surrounding wall, which can be evaluated with real-time ultrasound, especially during straining.

A term describing tissue or a mass that has a mixed, non-uniform appearance on ultrasound, with areas of different brightness throughout.